TASK 5 Flashcards
Humanity
Dominance hierarchies
- Some individuals are “higher” in rank than others and are constantly able to displace others from a resource
- dynamic ranking: can be challenged (by fighting) and reversed; higher ranks more stressed
- stable ranking: lower ranks more stressed
Social-brain hypothesis idea
= Machiavellian intelligence hypothesis
- maintaining social relationships requires devoted brain mechanisms –> social species will have larger brains compared to non-social ones
- bigger brain size must have evolved as a result of bigger group size
- only focus on social knowledge
Cultural intelligence hypothesis
- human’s unique cognitive skills is mainly due to species-specific set of social-cognitive skills for participating and exchanging knowledge in cultural groups
- humans only differ in cultural intelligence (proven in example with child and chimpanzee)
- can explain all knowledge (because it is derived from cultural intelligence)
General Intelligence hypotheses
- larger brains enable more efficient use of all cognitive operations
Adapted intelligence Hypothesis
- cognitive abilities evolve in response to relatively specific environmental challenges
- ecological theories and social theories combined
Bottleneck effect
- Sharp reduction in the size of a population due to environmental events or human activities
- African bottleneck: 172,000 years ago
- -> small set of ancestors expanded out of Africa
Allometry
= y = c * (w)^k
- Y (brain size) can be related to a more fundamental one W (body size)
- C and k are constants
- -> an increasing size does not have to result in an increase of its parts
Encephalisation quotient (EQ)
= (actual brain weight)/(brain weight predicted from allometric line)
- departure of brain size from the allometric line
Chihuahua fallacy
- Intelligence is too complex to have such a simple relationship
- small dogs (chihuahuas): body can be bred smaller but the brain size is less variable
Basic metabolic rate (BMR)
- rate of energy expenditure per unit time by endothermic animals at rest
- Metabolism: comprises processes that the body needs to function
Machiavellian intelligence hypothesis
- what differentiates primates from all other species was the complexity of their social lives and environment
- Machiavellian: misleading –> got replaced by the social brain hypothesis
Apomorphies
- traits that are defining for all species afterwards
- a novel evolutionary trait that is unique to a particular species and all its descendants
- can be used as a defining character for a species/ group in phylogenetic terms
Homology
similarity resulting from common ancestry (i.e. bones in hand and arm)
Convergent evolution
gain of new, similar features independently (trait that develops independently)
Pleistocene
- Ice Age = geological epoch that included the world’s most recent period of glaciations
= ‘winter’
Holocene
- Current geological epoch
- began after the last glacial period
= warm period, ‘summer’
Strepsirrhines
Suborder of primates that includes the lemuriform primates in Africa, Madagascar
Haplorrhines
“dry-nosed” primates, suborder of primates containing the tarsiers as a sister of the strepsirrhines
Prosimians
Group of primates that includes all living and extinct strepsirrhines and haplorrhines
Platyrrhines
- Group of primates that includes the new-world apes, marmosets and tamarins
- distinguished by having nostrils that are far apart and directed forwards or sideways and typically have a tail
Catarrhines
- Group of primates that include the old-world apes
- characterised by having nostrils close together with an opening in front of the face
Brachiation
mode of locomotion involving swinging from branch to branch using only arms
Hominins
- intermediate forms between chimpanzees and the humans today
- not a single evolving lineage –> branching of multiple forms, many of which go extinct and only some of which are on the line leading to living humans
Out-of-Africa model
- AMH is a new species that replaced the other living hominins without interbreeding
- Morphology: universal similarity; not Asians resemble Erectus more etc.
- Genetic evidence: deep branches between contemporary Africans
- -> African bottleneck: small set of ancestors expanded out of Africa
- Neanderthal DNA